1961—2007年黄土高原极端降水事件的时空变化分析  

Analyzing the Spatial-temporal Changes of Extreme Precipitation Events in the Loess Plateau from 1961 to 2007

作　　者：李志[1] 郑粉莉[2] 刘文兆[2] 

机构地区：[1]西北农林科技大学资源环境学院,陕西杨凌712100 [2]中国科学院水利部水土保持研究所,陕西杨凌712100

出　　处：《自然资源学报》2010年第2期291-299,共9页Journal of Natural Resources

基　　金：国家基础研究发展计划项目(2007CB407201);"十一五"科技支撑计划项目(2006BAD09B09)

摘　　要：极端降水事件会引起严重的灾害事件,其变化趋势需要进行详尽的评估。基于50个站点1961—2007年日降水数据,定义极端降水事件及衡量指标后,使用M ann-Kendall法评估了黄土高原极端降水事件的空间分布和时间变化特征。结果表明,极端降水事件的空间分布具有东南—西北方向的梯度变化特征,降水量、强度和年最大日降水量均从东南向西北递减,而严重干旱事件从东南向西北递增。多数站点极端降水事件的各指标都具有单一趋势,但各指标具显著性趋势的站点数差异很大。约40%的站点极端降水频率具有显著降低趋势;约30%的站点极端降水量的减少趋势和严重干旱频率的增加趋势具有显著性;约10%的站点极端降水强度的上升趋势和年最大日降水量的下降趋势显著。Extreme precipitation events （EPE） can result in severe hazards, and their changing trend needs to be assessed in details. Based on the daily precipitation data of 50 weather stations and the definition of EPE as well as the indices, the spatial distribution and temporal trends of EPE in the Loess Plateau of China during 1961 -2007 were assessed using Mann-Kendall method. Results showed that annual total amount, intensity and annual daily maximum precipitation amount decreased from the southeast to the northwest, severe drought events increased from the southeast to the northwest. Most stations have monotonic trends in indices of EPE during 1961 - 2007; however, the numbers of stations with significant trends are of great difference. About 40% of the stations have significant downward trend in frequency of EPE, 30% of the stations have significant downward trend in annual total amount of EPE and upward trend in frequency of severe drought events, and about 10% of the stations have significant upward trend in intensity of EPE and downward trend in annual daily maximum precipitation amount.

关 键 词：极端降水事件 黄土高原 Mann—Kendall 

分 类 号：P426.614[天文地球—大气科学及气象学] P429